A key need for border security is the ability for rapid visual assessment, verification, classification, and continuous tracking and localization of possibly multiple simultaneous threats, detected by wide area sensors such as radar, fence sensor, and local sensors (e.g., acoustics and under-ground seismic sensors).
Radar, fence, acoustics and seismic sensors provide the first line of threat detection capability, but do not provide visual feedback. Video-based visual assessment provides the necessary and the key mechanism for the operator-in-the-loop to make an assessment of the threat.
Video provides a complementary data source that can be used to verify detections by the non-visual sensors. This has the capability of significantly reducing the number of false alerts.
There is a finite time delay between an intrusion, dispatch of a response team, and eventual interception of the intruder. This time delay introduces ambiguity in the location of the intruder, which essentially impacts the ability of the response team to quickly intercept the intruder. Radar cued or standalone PTZ video based tracking and localization provides the necessary location and visual information to aid the responders to hone in on to the intruder quickly and with proper force and equipment to counteract the threat as assessed using visual inference.
Serious threats involving drug trafficking or terrorist transit typically involve multi-pronged intrusions, some of which serve as decoy to overwhelm the system to maximize probability of successful intrusion of desired elements. An effective system should be able to provide continuous assessment of multiple threats, with limited intervention of the operator.
PTZ cameras are routinely used in video surveillance applications to track activity over a wide area. Even though a single PTZ can pan all around (360 degrees), large areas of interests may get occluded due to buildings, trees and the like. As a result, an object being tracked may temporarily—or even permanently—get lost during a period where there is an occlusion.
Thus, there is a need in the art for a video surveillance method and apparatus that addresses this known problem of temporarily or permanently losing the activity or object being tracked by PTZ cameras due to occlusions.